From owner-freebsd-arch Tue Sep 12 14:19:56 2000 Delivered-To: freebsd-arch@freebsd.org Received: from peach.ocn.ne.jp (peach.ocn.ne.jp [210.145.254.87]) by hub.freebsd.org (Postfix) with ESMTP id 95DC137B424 for ; Tue, 12 Sep 2000 14:19:53 -0700 (PDT) Received: from newsguy.com (p21-dn01kiryunisiki.gunma.ocn.ne.jp [211.0.245.22]) by peach.ocn.ne.jp (8.9.1a/OCN/) with ESMTP id GAA18570; Wed, 13 Sep 2000 06:19:47 +0900 (JST) Message-ID: <39BE9DCE.857D2310@newsguy.com> Date: Wed, 13 Sep 2000 06:19:10 +0900 From: "Daniel C. Sobral" X-Mailer: Mozilla 4.7 [en] (Win98; I) X-Accept-Language: en,pt-BR MIME-Version: 1.0 To: Jason Evans Cc: Matthew Jacob , arch@FreeBSD.ORG Subject: Re: Necessary synchronization primitives (was Re: cvs commit: [...] yarrow.c [...]) References: <20000912161928.C23948@wantadilla.lemis.com> <20000912113445.F31089@blitz.canonware.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Jason Evans wrote: > > * Dijkstra semaphore > > I've gone through my library (including Knuth and various other books) > and the best I've been able to determine is that Dijkstra semaphores have > two operations: P (passeren: Dutch for "to pass") and V (vrijgeven: Dutch > for "to give free"). It is unclear to me given the references at hand > whether Dijkstra semaphores are generalized enough to include a count > like counting semaphores (described below), but I suspect so. Perhaps > Greg can shed some light on that. The original Dijkstra algorithm is a mutex, pure and simple. The counting semaphores comes from elsewhere. -- Daniel C. Sobral (8-DCS) dcs@newsguy.com dcs@freebsd.org capo@white.bunnies.bsdconspiracy.net OK, so the solar flares are my fault.. I am sorry, ok?!?! To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message